/*============================================================================

The Medical Imaging Interaction Toolkit (MITK)

Copyright (c) German Cancer Research Center (DKFZ)
All rights reserved.

Use of this source code is governed by a 3-clause BSD license that can be
found in the LICENSE file.

============================================================================*/

#ifndef MITKIMAGEPIXELWRITEACCESSOR_H
#define MITKIMAGEPIXELWRITEACCESSOR_H

#include "mitkImagePixelAccessor.h"
#include "mitkImageWriteAccessor.h"

namespace mitk
{
  /**
   * @brief Gives locked and index-based write access for a particular image part.
   * The class provides several set- and get-methods, which allow an easy pixel access.
   * It needs to know about pixel type and dimension of its image at compile time.
   * @tparam TPixel defines the PixelType
   * @tparam VDimension defines the dimension for accessing data
   * @ingroup Data
   */
  template <class TPixel, unsigned int VDimension = 3>
  class ImagePixelWriteAccessor : public ImagePixelAccessor<TPixel, VDimension>
  {
    friend class Image;

  public:
    typedef ImagePixelAccessor<TPixel, VDimension> ImagePixelAccessorType;
    typedef itk::SmartPointer<mitk::Image> ImagePointer;

    /** \brief Instantiates a mitk::ImageWriteAccessor (see its doxygen page for more details)
     *  \param Image::Pointer specifies the associated Image
     *  \param ImageDataItem* specifies the allocated image part
     *  \param OptionFlags properties from mitk::ImageAccessorBase::Options can be chosen and assembled with bitwise
     * unification.
     *  \throws mitk::Exception if the Constructor was created inappropriately
     *  \throws mitk::MemoryIsLockedException if requested image area is exclusively locked and
     * mitk::ImageAccessorBase::ExceptionIfLocked is set in OptionFlags
     *
     *   Includes a check if typeid of PixelType coincides with templated TPixel
     *   and a check if VDimension equals to the Dimension of the Image.
     *
     *  \note
     *  To avoid intermittent Update() calls to a predecessing filter pipeline, a call to Modifed() method after the
     * access is finished is left to the developer.
     */
    ImagePixelWriteAccessor(ImagePointer iP,
                            const ImageDataItem *iDI = nullptr,
                            int OptionFlags = ImageAccessorBase::DefaultBehavior)
      : ImagePixelAccessor<TPixel, VDimension>(iP.GetPointer(), iDI), m_WriteAccessor(iP, iDI, OptionFlags)
    {
    }

    /** \brief Gives full data access. */
    virtual inline TPixel *GetData() const { return static_cast<TPixel *>(m_WriteAccessor.m_AddressBegin); }
    /// Sets a pixel value at given index.
    void SetPixelByIndex(const itk::Index<VDimension> &idx, const TPixel &value)
    {
      unsigned int offset = ImagePixelAccessor<TPixel, VDimension>::GetOffset(idx);

      *(((TPixel *)m_WriteAccessor.m_AddressBegin) + offset) = value;
    }

    /** Extends SetPixel by integrating index validation to prevent overflow. */
    void SetPixelByIndexSafe(const itk::Index<VDimension> &idx, const TPixel &value)
    {
      unsigned int offset = ImagePixelAccessorType::GetOffset(idx);

      TPixel *targetAddress = ((TPixel *)m_WriteAccessor.m_AddressBegin) + offset;

      if (targetAddress >= m_WriteAccessor.m_AddressBegin && targetAddress < m_WriteAccessor.m_AddressEnd)
      {
        *targetAddress = value;
      }
      else
      {
        // printf("image dimensions = %d, %d, %d\n", imageDims[0], imageDims[1], imageDims[2]);
        // printf("m_AddressBegin: %p, m_AddressEnd: %p, offset: %u\n", m_WriteAccessor.m_AddressBegin,
        // m_WriteAccessor.m_AddressEnd, offset);
        mitkThrow() << "ImageAccessor Overflow: image access exceeds the requested image area at " << idx << ".";
      }
    }

    /** Returns a const reference to the pixel at given index. */
    const TPixel &GetPixelByIndex(const itk::Index<VDimension> &idx) const
    {
      unsigned int offset = ImagePixelAccessorType::GetOffset(idx);

      return *(((TPixel *)m_WriteAccessor.m_AddressBegin) + offset);
    }

    /** Extends GetPixel by integrating index validation to prevent overflow.
      * \throws mitk::Exception in case of overflow
      */
    const TPixel &GetPixelByIndexSafe(const itk::Index<VDimension> &idx) const
    {
      unsigned int offset = ImagePixelAccessorType::GetOffset(idx);

      TPixel *targetAddress = ((TPixel *)m_WriteAccessor.m_AddressBegin) + offset;

      if (!(targetAddress >= m_WriteAccessor.m_AddressBegin && targetAddress < m_WriteAccessor.m_AddressEnd))
      {
        mitkThrow() << "ImageAccessor Overflow: image access exceeds the requested image area at " << idx << ".";
      }

      return *targetAddress;
    }

    /** Returns a const reference to the pixel at given world coordinate - works only with three-dimensional
     * ImageAccessor
     */
    const TPixel &GetPixelByWorldCoordinates(mitk::Point3D position)
    {
      itk::Index<3> itkIndex;
      m_WriteAccessor.GetImage()->GetGeometry()->WorldToIndex(position, itkIndex);

      return GetPixelByIndex(itkIndex);
    }

    /** Returns a reference to the pixel at given world coordinate */
    void SetPixelByWorldCoordinates(const mitk::Point3D &, const TPixel &value, unsigned int timestep = 0);

    ~ImagePixelWriteAccessor() override {}
  private:
    ImageWriteAccessor m_WriteAccessor;

    ImagePixelWriteAccessor &operator=(const ImagePixelWriteAccessor &); // Not implemented on purpose.
    ImagePixelWriteAccessor(const ImagePixelWriteAccessor &);
  };
}
#endif // MITKIMAGEWRITEACCESSOR_H
